And thus, it ends. Despite a never-ending stream of doom and gloom from Oracle/Microsoft-funded 'pundits' regarding Google and Android (six hundred billion trillion gazillion eurodollars in damages!!1!), judge Alsup has just squashed all of Oracle's chances with a ruling that is good news for those of us who truly care about this wonderful industry: APIs are not copyrightable. Alsup: "To accept Oracle's claim would be to allow anyone to copyright one version of code to carry out a system of commands and thereby bar all others from writing their own different versions to carry out all or part of the same commands. No holding has ever endorsed such a sweeping proposition." Supreme Court, Ellison?

The legal doctrine is called "equitable estoppel". If you unilaterally promise something, you cannot then unilaterally withdraw that promise if, in doing so, you would cause harm to anyone who had relied upon that promise.

The classic case is this: you own a property in London. It is war-time, and you are finding it difficult to let the building. So you promise a potential lessee that you'll charge much-reduced rent for the duration of the war. The potential lessee agrees, and takes a lease. The war ends; you now say "you owe me the normal rent for the war years, which is much higher than the rent I actually charged you. And the war is over so you can afford to pay".

The English High Court, in 1947, basically said, "Bugger Off: you promise something, you can't go back on that promise if it causes detriment to someone who relied on your promise".

Microsoft promises not to sue in various circumstances; they cannot subsequently unilaterally withdraw that promise and hope to have their "rights" enforced.

And it's irrelevant if it's Microsoft or someone who has subsequently bought their patents or their patent right: Microsoft have renounced their patent rights in these specific circumstances. No-one may subsequently seek to enforce those rights, to the detriment of others, without bumping into the equitble estoppel brick wall.

The legal doctrine is called "equitable estoppel". If you unilaterally promise something, you cannot then unilaterally withdraw that promise if, in doing so, you would cause harm to anyone who had relied upon that promise.
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No-one may subsequently seek to enforce those rights, to the detriment of others, without bumping into the equitble estoppel brick wall.

What a funny little world you live in.

If you've kept up with the "developments" of the legal system in recent decades, you know that a big company does not ever need to win in order to wield their power. All they need is a large sack of cash and lawyers and either intimidate or appeal endlessly until the other guy runs out of money. The threat of that alone has already forced many small players into undisclosed out of court settlements.

So again, while we all would like to live in a world where the side who is right is the side who wins, the real world favours the side with the money.

Not so funny. Just the way it is. Promissory or equitable estoppel (or 'detrimental reliance') is so well established as a legal doctrine, both in the UK and the USA to name but two, that I don't care how big the company is or how many lawyers they hire: they're not going to win.

There are no legal developments in recent decades that make it a grey area. Quite the opposite: the doctrine is much more firmly developed now than it was, say, 60 years ago.

Whether it takes a 25-pound postal order, self-representation and a district court magistrate or two years and a large team of highly-paid barristers is really irrelevant to the issue at hand: you said "it's Microsoft and can we really trust any of their promises"... and my point simply is, trust doesn't come into it. The matter is justiciable, and that's all that really counts.

You appear to believe that the law is abused by big business merely to intimidate the little guys. I happen to believe, with good reason, that it's actually the law that *stops* big business trampling all over the little guys.

I personally don't think that's particularly naiive, but even if you do, it doesn't alter the fact that promises not to sue can't be withdrawn on a mere whim or without legal consequences.